The IUE INES System: Improved data extraction procedures for IUE

¹ Departamento de Física, Universidad Europea de Madrid, C/Tajo S/N, 28670 Villaviciosa de Odón, Spain
² LAEFF, P.O. Box 50727, 28080 Madrid, Spain
³ ESA - XMM SOC, P.O. Box 50727, 28080 Madrid, Spain
⁴ ESA - IUE Observatory, P.O. Box 50727, 28080 Madrid, Spain

Send offprint request to: P.M. Rodríguez-Pascual

Received: 1 March 1999
Accepted: 28 June 1999

Abstract

We present the extraction and processing of the  Low Dispersion spectra within the framework of the ESA "IUE Newly Extracted Spectra” () System. Weak points of , the optimal extraction implementation to produce the  output products (extracted spectra) are discussed, and the procedures implemented in  to solve these problems are outlined. The more relevant modifications are: 1) the use of a new noise model, 2) a more accurate representation of the spatial profile of the spectrum and 3) a more reliable determination of the background. The  extraction also includes a correction for the contamination by solar light in long wavelength spectra. Examples showing the improvements obtained in with respect to are described. Finally, the linearity and repeatability characteristics of  data are evaluated and the validity of the errors provided in the extraction is discussed.